判断网络是否连接

/**
 * 检测程序运行时,当前网络是否连接
 *
 * @return
 */
public static boolean isNetworkConnected(Context context) {
   if (context != null) {
      ConnectivityManager mConnectivityManager = (ConnectivityManager) context
            .getSystemService(Context.CONNECTIVITY_SERVICE);
      NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
      if (mNetworkInfo != null) {
         return mNetworkInfo.isAvailable();
      }
   }
   return false;
}